Full Floater

6 hours ago, Vladislav said:

Thanks for the note. I'm going to revise my Ambac pump off E6-350. The idle was floating and the rest seemed Ok. But bench check and other possibly needed jobs are on the list.

I will Google the "rack buffer" to figure more about the issue you fought. 

There sure isn't a lot of info out there.   

Old topic, but a common issue.   

I just had an Ambac pump rebuilt solely due to worn gov springs/surging at low rpm/low throttle input.   A rack "buffer" kit was installed in conjunction with whatever else they did to the governor.    Solved the surging problem completely.

I have 3 others with the same problem, and will eventually get all 3 of them done also when funds permit.   Should be good for another 40-50 years now.

Reliability and longevity wise, is the V pump equally as capable as the inline pump?

On 2/13/2024 at 7:52 AM, mechohaulic said:

system should have a filter, by chance did you change fluid and filter ?? going by all the torque specs given ; hopefully wheel might feel better just make sure adjustments aren't TOO tight.  after driving and system heats up and expands  ; wheel doesn't bind up while driving creating serious situation. tad amount of free play needed.

Yes the system does have a filter.   I have recently replaced it and the fluid along with all the power steering hoses.  I used 15w40 engine oil as per recommendations from somewhere here on a different topic in discussion.  I also used a few ounces of Lucas Power Steering additive.

Seems  like I got it!   I'll know after some more driving, but so far on test runs, it's tightened up.

8 hours ago, glenbjackson said:

the adjusting screw should be on opposite side than the pitman arm, other end of sector shaft frame side! should be a screw in center of cap.

screw is tightened to no lash, which is measured with torque wrench AT INPUT shaft while rotating side to side(15-20lb in) . then back out one turn and tighten for a tightness of 2-4lb in at the input shaft while turning it side to side, pass center. Center must be passed for correct adjustment, highest and tightest point is the center.  Next tighten Jam nut to 20-25lb FT.

lastly check by rotating input shaft through entire travel back and forth five cycles. properly adjusted will not exceed 15lb in at input shaft. 

check "reverse torque" through the OUTPUT shaft, full travel should not exceed 50lb FT!

 

 

MANY thanks!   Great info!

So just to clarify, when  you say "center must be passed" for correct adjustment, does this mean the wheels need to be turned to one side, as long as it's beyond center of of the range of travel? 

My main questions are:

Does the pitman arm NEED to come off for proper adjustment?

And does the set screw get adjusted in the "center" of steering movement where there is the most play, or with the steering turned to one side?   I'm reading conflicting info on the old "www"

It's never a bad idea to run an air dryer.   You can run a conventional readily available model like a Bendix AD-9.  Doesn't have to be Mack.   

I have this Ross steering box on this 75 R685 Western.  The steering is just a tad too loose.  It's not nearly as bad as some that I have driven.  If I could tighten it up just a bit, I would be happy.    What is the/is there a procedure for this box?

Should we/are we supposed to run a high ZDDP 15w-40 oil in our older engines?  I have 5 675's and have always run whatever 15w-40 I can get locally, usually Walmart brand; and change it a little more often then some might.   Never had an issue.   But as things wear and get older, and oil specs change....do we need a certain ZDDP content or additive to help out in the wear department? 

It would probably be fine, but without an aluminum rad (which I doubt you have) nitrite free coolant isn't doing you any good.   The nitrite containing coolant offers better cavitation protection, so they say.   My main choice for all diesels, and I have quite the fleet of old iron; is...   I've been running it in everything for well over a decade.  Maybe 2 decades now

https://www.tenaquip.com/product/prestone-command-heavy-duty-esi-concentrate-antifreeze-coolant-378-l-jug-74005-flt537

Any reason not to run 75w-140 in a 6 speed?

One of mine is well worn out and is hard to shift when hot.   Shifts good when cold (think oil) but i'd like to put something in it with a higher viscosity when at operating temp.   So I was thinking 75w-140 and some Lucas.

Put on a new Borg Warner 4le-292 from J&H Diesel in Greenville MS.   Not sure if this turbo that's listed for a 285 is too big of turbo for a 237 that has stock fueling, and its actually hurting performance, but I have nothing to compare it to and it seems to be running fine.

Ok thanks.   And i'm assuming its safe to increase RPM to speed up the pto?

Thanks.   So both boxes in Neutral and increase RPM for higher pto speed?

On 4/30/2023 at 4:28 PM, mechohaulic said:

another thought based on yrs back ;the rear mount P T O 's  on 6 speeds were constant run when engaged with truck moving or stationary. the side mount 6 speed  pto worked off trans being in gear on main. pto speed depended on gear main was in. spreading asphalt was challenging :: truck had to be in low for spreading which was tooo slow for dump/PTO operation. thus the rear mount pto came to be. 

Just want to clarify "proper" operation of my rear mount PTO on this 6 speed.   The Mack instructions on the dash, say to engage PTO with aux in N and main in gear.  I'm thinking this was likely for a side mount PTO and maybe it was changed to a rear mount, later in life.    As this one spins if the main trans is in N also, OR in gear.  I don't notice any difference in hyd power or speed if a high gear is engaged, nor do I visually notice the PTO shaft spinning faster or slower. 

So with a rear mount, should I still have the main box in gear and aux in N?  Or both in N?  Am I to use engine RPM to spin the PTO faster if using a higher gear doesn't seem to achieve much.

On 11/17/2023 at 3:13 AM, JoeH said:

I've never bothered using mine, not even sure they work on our trucks.  I believe they open facing the windshield. Cold temps I just run the fan. Summer I use the roof and side vent plus the driver wing window.  

Thanks.   Ya they seem redundant....I feel like they should do at least a little something otherwise they wouldn't be there, kinda like a Dynatard.   But maybe not.

Pyro.

Fuel pressure gauge is another informative gauge that gets overlooked.   Can really show a problem coming before you're stuck on the side of the road.

Seems as most older Macks use a 10psi 2-5/8'' neck rad cap.

Has anyone ever put a lower psi rad cap on, for reduced strain on old cooling systems?  Or even a 0 pressure cap.  I have done this on SEVERAL old vehicles including diesels (wet sleeved and parent bored) and have never had any negative results and very few cooling system related issues and no blow outs of things like hoses and heater cores and such....which is what im concerned about.

Yes, I realize that lowering the psi also lowers the boiling point of the coolant, which is fine by me as I drive with 1 eye on the gauges and never let it get anywhere close to hot.

Any thoughts?  Cavitation?  Hot spots?  

Thanks

2 hours ago, Geoff Weeks said:

Depends, on type and which adjustment you are talking about. If you are adjusting for wear at the ball socket, then no. If you are adjusting for length then it depends on how the drag link is made. Some like my Marmon use a mini tie rod with left and right threaded ends, and that can be adjusted for length without removing an end, others like my IHC's and I think yours (hard to tell from the picture, but it looks to have only one thread) you have to remove one end to thread it in or out.

Ok thanks, ya im just trying to adjust for wear.  

Stupid question, but these can remain all together (not separating the ball joint) for adjustment, right?

So....the sticker on my factory heater blower motor says to use the cowl vent for ram air heating.  When I have the cowl vent open (there are no obstructions in it that I can see) I have very little ram air effect coming in even at highway speeds, so I end up having to use the fan anyways.

Am I missing something here in the cowl operation?  Is it normally as effective as the sticker makes it out to be?  Would be nice to have ram air instead of using the fan.

Thanks

1 hour ago, terry said:

Maybe was changed by a previous owner, trying to give it a little more power?    terry

I would assume.  

I have a Borgwarner 4LE-292 Turbo on a stock and stock fueled 237.  The impeller has a few chunks missing out of it and i'd like to replace the turbo instead of just the compressor wheel, as it's probably due anyways.    I know this topic has probably been beat to death, but is there a current "better" option out there for bolt on turbos?  I don't want to alter any piping or anything, nor do I want to increase the fueling rate.  And im not looking to make more power.  Just curious if there is something out there that modern technology has refined, made more efficient etc..., that would be worth looking at.    Reliability and longevity are key....but if we can reduce exhaust smoke a bit and maybe squeeze half a mile per gallon out of it, that would be swell.

One thing of note that im finding as I internet search the 4LE-292 turbos.  It gets listed as a turbo for a 285, opposed for a 237 which comes up as a 4LE-303.   Any insight on this?